Three Point Charges, Find x-component

1. The problem statement, all variables and given/known data
In the figure, three point charges are arranged in a equilateral triangle of side a= 1.40×10-2 m. Sketch the field lines due to + Q and -Q, where Q = 2.50×10-5 C , and from them determine the direction of the force that acts on +q = 5.00×10-8 C because of the presence of the other two charges. What is the x-component of the force? What is the y-component of the force?

2. Relevant equations
F1=K*((Q*q)/a^2)
F(x)=2|F1|*Cos(60)

3. The attempt at a solution
I know that the y-component is 0 N.
Someone posted this problem in yahoo answers, and I tried to follow it. Something went wrong along the way, but here is the work from that solution: